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Cichlidae posted:That's called rutting, and it's caused by heavy loads and using an insufficiently rigid asphalt binder that deforms in hot weather. In Rhode Island, the rutting gets so bad that the loop detectors themselves are crumpled into postage-stamp shapes, with the rippled edges. Funny trivia about rutting: It actually gets worse the slower vehicles drive. This is because asphalt is a visco-elastic material. In layman terms, it's a bit like water: pretty drat hard if you smack into it face first from 10m, soft if you gently roll into it. This is why pulling in to a bus stop will scrape your exhaust pipe off. Unless the stop sits on a concrete plate. Jasper Tin Neck fucked around with this message at 01:31 on Nov 11, 2009 |
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Nov 11, 2009 01:29
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Nesnej posted:Funny trivia about rutting: It actually gets worse the slower vehicles drive. This is because asphalt is a visco-elastic material. In layman terms, it's a bit like water: pretty drat hard if you smack into it face first from 10m, soft if you gently roll into it. This is why pulling in to a bus stop will scrape your exhaust pipe off. Unless the stop sits on a concrete plate. Makes sense, then, that most rutting happens at the upstream approach to an intersection. We had several classes on the viscoelastic properties of asphalt binder, complete with some horrible differential equations and plenty of graphs. By the time we got to Superpave, I was so overjoyed at how (relatively) simple and straightforward the tests were, that I immediately forgot all the viscoelastic stuff. Good thing it wasn't on the final.
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Nov 11, 2009 18:27
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There's an intersection near my work, which has several 18 wheelers go through it every day, and it has a stop sign on a somewhat steep downhill grade. I wish I could take a picture of just how ridiculously bumpy the pavement is right before the stop sign. It's bumpy.
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Nov 11, 2009 18:31
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Cichlidae posted:Makes sense, then, that most rutting happens at the upstream approach to an intersection. We had several classes on the viscoelastic properties of asphalt binder, complete with some horrible differential equations and plenty of graphs. By the time we got to Superpave, I was so overjoyed at how (relatively) simple and straightforward the tests were, that I immediately forgot all the viscoelastic stuff. Good thing it wasn't on the final. Tell, me about it, I'm having a course on the topic right now. It's been a fairly interesting course though. The visit to the laboratories of the Danish national road institute was particularly interesting. It's too bad I didn't take a camera with me, because they had all kinds of wacky equipment, including one designed to simulate rutting on new road sections. They simply cut out a 1x1m piece of a freshly paved road segment, bring it to the lab, mount it in a frame and put it on a foundation that offers a standard amount of support. Then they put it into this machine that rolls a truck tyre with half the force of a standard axle over the 1x1m piece of asphalt for two weeks 24/7, simulating about three years worth of traffic. Did I also mention the room it is in gets heated up to 80°C while the foundation is kept at 20°C to simulate summer weather? Because it is. It's really ridiculously thorough, the truck wheel even gets shifted around horizontally according to a normal distribution so that it doesn't roll over the same place all the time.
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Nov 11, 2009 21:07
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This is an awesome thread, I've read the whole thing over a few days. I'm doing a public health PhD trying to link urban environments, active transportation and cardiovascular disease so getting the point of view of a traffic engineer is quite informative. I've got a few things from Adelaide, Australia that you might be interested to see but first I thought I'd mention this from pages back because I love this piece of trivia: Cichlidae posted:Finally... Batman Avenue? Fun Melbourne history: the city's site was probably first chosen by John Batman, who declared that it should be called Batmania. Unfortunately they changed it, can't blame them I guess as it had accumulated a number of other less exciting names too. Wikipedia posted:Both Batman and Fawkner settled in the new town, which had several interim names -- such as Batmania, Bearbrass, Bareport, Bareheep, Barehurp and Bareberp (in June 1835)[5][6] [7] -- before being officially named Melbourne in honour of the British Prime Minister, Lord Melbourne, in March 1837. Ok, so I live in Adelaide - a city of about 1 million people with TERRIBLE urban sprawl, because we have a ton of space and relatively cheap fuel. Luckily there's also almost no city centre so we don't have too bad traffic problems. Having said that, anyone who lives east of the city will know this particularly awful roundabout :  It's called the Britannia roundabout and serves 2 of the busiest roads - heading right to left is a major commuter path from suburbs to the city, and bottom to top runs along the eastern side of the city, very popular with people who need to cross the city but don't want to go through it. It's 2 lanes, quite large and can be pretty confusing for anyone who isn't used to it. Accidents occur regularly when people realise they're not in the correct lane for where they want to go and decide to switch, especially during peak hour because up to 3 entry lanes can be backed up at once, causing people to become less careful lest they miss the 5 second space for them to enter. Worst of all though is the afternoon path from left to right. The cars in pink have to give way for the cars in green at two distinct spots, so an island was put in to split up the process of entering the roundabout, but that just means that pink cars end up having to give way to cars turning on the roundabout as well as watching out for aggressive drivers on their left (who often cannot see anything but the cars waiting at the island). It's also really hard to tell if the green cars are going straight or turning (people indicate very late, if at all). So what would you do to fix it? There were some plans 4 or so years ago but they got shelved for costing $100 million. You can't cut off any of the roads either, the mostly useless one up the top serves a well-off suburb and shopping area, no doubt they would raise hell. A more recent thing that makes me laugh and  at the same time is the Frome Road bicycle path. Here's Frome Road: The intersection is very busy for adelaide - the other road is a 6 lane boulevard that goes straight through the city and always has a good amount of traffic on it. On the left and right of frome road are two universities, a medical school and a hospital, so there's always plenty of pedestrian, car and cycle traffic on that road too. Both have busy bus schedules. Given the university demographic it's not surprising that Frome Road had a bike lane - I've drawn the old one in pink. Like every bike lane here in Adelaide it's just a pair of lines painted on the road. Anyone who has tried them knows they're not that great - they're not very wide, you're still right next to cars, and parked cars will either cover up the bike lane or be right next to it, ready to door you. Still, at least one side of the road had a bike lane, the other was even worse - very busy at peak hour, very little room for cyclists and a high curb made it awful to ride along. Someone must have really pushed the council because not only did they install a bike lane on the other side of the road, they didn't even do it the old way - they instead covered up half the sidewalk with a new purple-coloured-paint bike lane. You can see it here, I've highlighted the paint signs telling cyclists which part is their one-way lane and pedestrians that they can walk both ways.  Unfortunately that's the extent of their effort. The green line I've indicated on the aerial picture is the entire length of this new bike path. Pedestrians constantly walk along it with no regard for cyclist right of way, and cyclists go both ways down the one-way path because it is of course much safer than using the crappy one on the other side of the road (I've personally been hit by a car on the old one). It's kind of nice that maybe we're moving towards separate car/bike lanes but everything else about it is so half-assed I can't help but cringe. Adelaide is very flat, the city layout is actually pretty well designed, it should be a great cycling city but the infrastructure and transport attitude is really outdated here. I've seen good signs lately though so here's hoping. On a more positive note, we have what Wikipedia says is the world's longest reversible highway lane (21 km/13 miles), it seems to function pretty well.  It's not like the ones you talked about before though - it's completely separate and all three lanes go the same way at any time of the day. Wikipedia posted:The Southern Expressway is open approximately 22.5 hours per day - a one-way freeway operating for over 11 hours in each direction. The northbound direction occurs on weekday mornings and weekend evenings, the southbound direction occurs on weekday evenings and weekend mornings. It is closed between approximately 12:40am – 1:10am and 12:30pm – 1:30pm, except for Saturday and Monday mornings when the direction remains unchanged. The official closing times given by Transport SA are between 12:30am – 2:00am and 12:30pm – 2:00pm. During each closure all road signs, lights and boom gates switch, and the road is inspected by a tow truck contractor for debris and car breakdowns. You can see the northern entry/boom gates here:  Clearly this would only work somewhere with as much space as we have to play with though, most of it runs through what would otherwise be empty (farming, possibly) land. Bubble-T fucked around with this message at 21:13 on Nov 11, 2009 |
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Nov 11, 2009 21:11
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Socket Ryanist posted:There's an intersection near my work, which has several 18 wheelers go through it every day, and it has a stop sign on a somewhat steep downhill grade. The worst in my jurisdiction is Route 287 at Route 15. There's a hill beforehand, so the signal is mostly hidden, and then about 200 feet of steep downhill grade to the stop bar. Drivers are going about 45-50 mph, then see the signal and have to brake. Because of this, the pavement has HUGE ruts and is so bumpy that it feels like you're driving down stairs. My boss had a project there years ago, and had a really hard time shifting traffic because their wheels kept slipping into the old ruts. nesnej posted:Tell, me about it, I'm having a course on the topic right now. It's been a fairly interesting course though. Huh, over here we just use gyratory compactors. Heck, in most places, Marshall Mix is still the norm, and that was designed for building airbases on pacific islands in World War Two. Science? Wuzzat? 
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Nov 11, 2009 23:00
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Cichlidae posted:Huh, over here we just use gyratory compactors. Heck, in most places, Marshall Mix is still the norm, and that was designed for building airbases on pacific islands in World War Two. Science? Wuzzat? Speaking of which, we discussed maintenance policy in class a few weeks ago and our professor mentioned that in the US it's pretty common for the DOTs to even dictate what kind of mix the entrepreneur should use and that once the road is built, it's the DOTs responsibility to maintain it. Is there any specific reason why things are done like that instead of just outsourcing maintenance in 10-year periods based of functional criteria like they do here, bar tradition?
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Nov 11, 2009 23:17
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Bubble-T posted:Fun Melbourne history: the city's site was probably first chosen by John Batman, who declared that it should be called Batmania. Hot drat, talk about missing a golden opportunity! Bubble-T posted:Ok, so I live in Adelaide - a city of about 1 million people with TERRIBLE urban sprawl, because we have a ton of space and relatively cheap fuel. Luckily there's also almost no city centre so we don't have too bad traffic problems. Having said that, anyone who lives east of the city will know this particularly awful roundabout : Looking around, I noticed that it's part of a street circuit. That necessitates keeping the freeflow right intact. It'd be possible to fix this up by reducing it to two signalized intersections, but it would break up route continuity on either A21 or the east-west road. Another option would be to stick in two roundabouts, or tee up Wakefield Road with Dequetteville Terrace just to the west of a revised, smaller roundabout at a new signalized intersection. The downside to this plan is that some properties on the east side of the circle may need to be demolished. With more money, I'd sink A21 into a tunnel, so that through traffic wouldn't have to enter the circle at all. This is a pretty common treatment in many parts of the world, and it'd preserve the nature of the traffic circle while enabling it to handle higher volumes. As to whether it could be done for under $100 million, well, it'd be close. It all comes down to deciding whether or not the improved operation is worth it. Bubble-T posted:A more recent thing that makes me laugh and We can hope that, should the new bicycle lane be successful, it could be expanded and implemented on other streets. More enforcement to keep peds out would certainly help. Bubble-T posted:On a more positive note, we have what Wikipedia says is the world's longest reversible highway lane (21 km/13 miles), it seems to function pretty well. Wow, that's a freeway by itself, not just some extra lanes on an existing facility. The interchange design (using roundabouts as the junctions) is pretty nifty, with gates to discourage wrong-way entry. The bike path alongside is cool, too. I can only imagine how well something like that could cut down on peak hour traffic if we had one here. Thanks for showing me!
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Nov 11, 2009 23:19
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Nesnej posted:As I said, it's ridiculously thorough, but for some reason Denmark likes to do these kind of things. Marshal tests are the standard for setting pavement specifications though. I'd imagine that would open the door for horrible contractors to come in, lay down low-quality asphalt, get paid, and immediately book it to Grand Cayman Island or the like. Many many contractors don't last more than a few years between "reorganizations" (change the name, hire a new CEO, ignore any previous responsibilities). It's also nice to have a uniform pavement structure for a given facility, so when we have to do utility/maintenance/ITS work, we know what's down there. In Connecticut, we specify our job mix formula using Superpave (Rhode Island still uses Marshall) and contractors have to meet the spec with independent testing. After all, Superpave really is just a series of performance-related tests. Why give the contractor lots of lenience, and the potential for loopholes, when we can just go with international standards?
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Nov 11, 2009 23:25
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Cichlidae posted:With more money, I'd sink A21 into a tunnel, so that through traffic wouldn't have to enter the circle at all. This is a pretty common treatment in many parts of the world, and it'd preserve the nature of the traffic circle while enabling it to handle higher volumes. As to whether it could be done for under $100 million, well, it'd be close. It all comes down to deciding whether or not the improved operation is worth it.  Cichlidae posted:We can hope that, should the new bicycle lane be successful, it could be expanded and implemented on other streets. More enforcement to keep peds out would certainly help. Unfortunately they just did a whole revamp of the main road there (North Terrace) and while it looks really nice now I think they missed a golden opportunity to add a proper bike path (the sidewalks are pretty wide much of the way). Cichlidae posted:Wow, that's a freeway by itself, not just some extra lanes on an existing facility. The interchange design (using roundabouts as the junctions) is pretty nifty, with gates to discourage wrong-way entry. The bike path alongside is cool, too. I can only imagine how well something like that could cut down on peak hour traffic if we had one here. Thanks for showing me! anyway thanks for this thread, it's really cool. I don't know whether you saw it but a goon called apathetic poster did a big megathread in LF on urban planning which was lots of fun to read too, I can try and find it if you'd like? edit: oh whoops, it was sitchensis who started it because apathetic poster had been too lazy or something http://forums.somethingawful.com/showthread.php?threadid=3090821 Bubble-T fucked around with this message at 23:35 on Nov 11, 2009 |
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Nov 11, 2009 23:32
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Bubble-T posted:I think tunnels were considered and would be cool but it's just one of those problems where everyone yells about fixing it once a year and then shuts up when they realise the costs involved. I'm guessing this is something you get used to in that field I had some free time and did a quick sketch of what it would look like with a tunnel. I also teed up the two roads at a signal to get rid of crossing traffic to the west of the circle, but that's optional.  Also, someone earlier (GWBBQ?) asked about that intersection in Fairfield with the Black Rock Turnpike and Route 1 under Route 95. I chatted with someone in our project concepts area (it's his job to deal with this stuff), and he had basically the same conclusions as you and I did. After a lot of work, he settled on turning Johnson Drive into a one-way-eastbound street and replacing the big circle with four small roundabouts with two-way roads between them. Of course, the volumes were too big, so it wouldn't work. Looks like Fairfield's pretty much stuck with that big circle.
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Nov 12, 2009 00:21
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Cichlidae posted:I'd imagine that would open the door for horrible contractors to come in, lay down low-quality asphalt, get paid, and immediately book it to Grand Cayman Island or the like. Many many contractors don't last more than a few years between "reorganizations" (change the name, hire a new CEO, ignore any previous responsibilities). It's also nice to have a uniform pavement structure for a given facility, so when we have to do utility/maintenance/ITS work, we know what's down there.
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Nov 12, 2009 01:08
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Man, I wish I'd found this thread earlier. I'm a complete road geek and just spent 4 hours reading this. I'm one of those idiots that has a copy of the MUTCD just because. Anyway, you mentioned Kurumi a couple times, along with saying you want to get to know our cities. Figured I'd drop some road porn on you. Feel free to move that map around, it's bigger than I can fit - it's the Spring-Sandusky interchange in Columbus, OH, started in the 50's, hosed up in the 70's and finished about 5 years ago. Yeah, this is the fixed version you see here.  Click here for the full 1535x738 image. It actually works for about 21 hours/day. I'd call that a great success over what was there before and usually tell folks to quit bitching because there is no real traffic problem here. Thanks for the fascinating read. Edit: Here's what the silly part of that interchange used to look like Halah fucked around with this message at 02:33 on Nov 12, 2009 |
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Nov 12, 2009 02:05
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Halah posted:Man, I wish I'd found this thread earlier. I'm a complete road geek and just spent 4 hours reading this. I'm one of those idiots that has a copy of the MUTCD just because. There's nothing uncool about having a copy of the MUTCD, as long as you don't tell anyone about it  quote:Anyway, you mentioned Kurumi a couple times, along with saying you want to get to know our cities. Figured I'd drop some road porn on you. Feel free to move that map around, it's bigger than I can fit - it's the Spring-Sandusky interchange in Columbus, OH, started in the 50's, hosed up in the 70's and finished about 5 years ago. Yeah, this is the fixed version you see here. The interchanges themselves have some substandard elements (left exits/entrances, broken route continuity, weaving sections), but any city the size of Columbus should consider itself lucky to have a full beltway, let alone two! I can certainly imagine how it could've been worse before; take out a couple ramps, and only a seasoned regular would be able to find his way around. Edited to add: Just looked at the historical pic, and drat, that's some old-school freeway design. Looks like someone just started with a boulevard and tossed in ramps wherever they would fit.
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Nov 12, 2009 02:36
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Nesnej posted:Speaking of which, we discussed maintenance policy in class a few weeks ago and our professor mentioned that in the US it's pretty common for the DOTs to even dictate what kind of mix the entrepreneur should use and that once the road is built, it's the DOTs responsibility to maintain it.  "contractor"
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Nov 12, 2009 13:56
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Can any of you tell me why, when repaving the freeway they don't repave the overpasses/bridges/elevated sections? It's annoying as hell and I'm sure there's a reason for it, my thought was due to the extra weight?
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Nov 12, 2009 21:48
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Nebulis01 posted:Can any of you tell me why, when repaving the freeway they don't repave the overpasses/bridges/elevated sections? It's annoying as hell and I'm sure there's a reason for it, my thought was due to the extra weight? Bridges are generally made of concrete, whereas the rest of the road is asphalt on top of gravel. Yes, adding extra asphalt could compromise the bridge's integrity, and that's been the case on several projects. Most of it, though, is that milling into concrete's generally not worth the effort, since the asphalt overlay is generally in better shape than the asphalt on gravel. The bridges get overlaid less often this way. Of course, it leads to a patchwork structure, looks ugly, and is annoying to drive over. It's always a fine line between improving ride quality and wasting money when there are more important segments to pave.
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Nov 12, 2009 22:18
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Is preserving the integrity of asphalt on concrete (I assume it's thinner than on gravel) why bridges don't have rumble strips on the shoulders?
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Nov 12, 2009 22:53
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GWBBQ posted:Is preserving the integrity of asphalt on concrete (I assume it's thinner than on gravel) why bridges don't have rumble strips on the shoulders? I'm not sure why, it could also be that the rumble strip machine can't cut into concrete as well. Or, it could be because rumble strips occasionally need to be removed (to run traffic in the shoulder, for example), and removing rumble strips from concrete, which involves milling out a whole strip and pouring new concrete, is super tricky. Think of all that rebar!
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Nov 12, 2009 23:36
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Here is a book that many of you will enjoy: Houston Freeways. This guy is apparently a freeway nut, wrote a book about Houston's freeway system, and self published it. More importantly, he has the entire book available as a pdf on the site. Very good read, and lots of history about our amazing freeway system.
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Nov 13, 2009 03:19
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How would you have designed this exchange? (Riverside/Heron/Airport Parkway, Ottawa, ON) This has always struck me as an overly complex configuration of on- and off-ramps wasting potentially useful space. There's a dangerous weave on the east side of the Airport Parkway, especially for those headed from northbound Airport Parkway to eastbound Riverside. The other annoyance, at least from my point of view (I live to the south of this whole area and take the Airport Parkway home frequently) is that in order to get southbound on the Parkway from either Heron or Riverside, one needs to travel further south to the Brookfield on-ramp. The railroad track is an obvious impediment to a more "standard-looking" interchange at Heron, but as it's currently only used by a public transit line, I feel that it could have its alignment changed if the neighbourhood warrants a proper transit hub. The buildings surrounding this area are all federal government offices, and I think this whole neighbourhood could be transformed into a transit-oriented development hub when the government buildings reach the end of their life expectancy, but provided the transportation network and transit are reworked. What do you think?
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Nov 15, 2009 23:03
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aquil posted:How would you have designed this exchange? (Riverside/Heron/Airport Parkway, Ottawa, ON) Well, one of those buildings is a classified federal heritage building, and another one is the headquarters of a rather important intelligence agency, so they'll be around for a long time. However, there's plenty of room for some nice dense mixed-use development, and the location seems good, with so many high-capacity arterials nearby. As to the interchanges, the weaving zone isn't on the mainline itself, so that's not a big concern. A bigger issue is the lack of a full interchange; there's no access to Airport Parkway southbound. As you said, the railroad tracks make this difficult, but it wouldn't be terrifically difficult to add a ramp and widen the bridge over the tracks. I'd also get rid of the trumpet interchange south of there if the volumes were low enough, as they're really not best in that situation. There's no simple design that works well with the existing geometry and site conditions, though, as you mentioned, it has more ramps than it needs. The two-lane crossover on Heron Road could just as easily have been left out; a jughandle at Data Centre Road and left turn lanes at Riverside Drive would accomplish much the same thing. Removing the freeflow right turn lanes between Heron and Data Centre would get rid of a small weaving area on Heron, increasing safety but decreasing capacity. Overall, there are a lot of improvements that could be done, but I'm not sure if it's worth the money and time it would take to do them. As to what I'd have done if I were designing it for the first time, I would probably have put one-way frontage roads on both sides of the freeway with slip ramps effectively making a diamond interchange. If volumes were too high, a pair of parclos with collector-distributor roads (similar to what exists now) would work. Edit: Hey check it out! It fits with the current arrangement, uses a lot of the existing roads, and even looks elegant. I put in a two-way underpass to provide better access to the Drake Building and Data Centre, and cut down trip distances. 
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Nov 15, 2009 23:28
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 What kind of "New Traffic Patterns" warrant the use of this sign? When I saw this sign I imagined we would be driving on the left or backwards or something. In reality I don't think anything changed.
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Nov 16, 2009 00:28
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Interesting thread! In the north of the Netherlands, two highways meet in the south of the city of Groningen, at this intersection:  (or on Google for Street View) It's an at-grade crossing with signals, originally designed in the 50s. The way north goes towards the city centre, there's highways coming in from the west and south which connect the city to the rest of the country, and the east road is for traffic to Germany or to the east of the city (lots of jobs there). Oh, and the east and west roads also function as the city's ring road. Needless to say, it's a huge mess around rush hour. There have been all kinds of plans to fix it that didn't work out, either because of the surrounding city or the natural landscape to the south of it. It also doesn't help that there is a channel right next to it, which needs to have a drawbridge for boats with standing masts. I'm not sure what the park-like bit in the south-east is for, but I don't think they'll want to pave that either. Some years ago they removed the option of turning left into the city from the west highway, but that didn't seem to help much. And that change was only possible thanks to a new bus lane providing a shorter route for the buses. The road north leads directly to the main bus/train station, making it undesirable to limit access to and from there. What would you do about this?
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Nov 16, 2009 00:45
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What needs to be "fixed"? Most intersections of highways in america look like that and work just fine!
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Nov 16, 2009 01:07
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Guy Axlerod posted:
It's mostly just a "pay attention" sign. The change in traffic patterns might be subtle (protected-permitted phasing instead of protected-only, for example), but it could lead to a nasty accident if someone wasn't aware that the signal had changed. Think of it from the DOT's viewpoint and how big of a liability it would be if someone got in an accident from a slightly revised signal or the like.
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Nov 16, 2009 01:53
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Entropist posted:Interesting thread! When a normal signalized intersection can't handle the traffic using it, the easiest way is to add lanes. Beyond a certain point (and this intersection is pretty much there,) things need to get more exotic. You can screw around with phasing by forbidding left turns, adding jughandles, or making it a continuous-flow intersection, but even that has its limits. Soon or later, if the volumes keep increasing, it's time to grade-separate that mofo. There are a lot of options when it comes to grade-separation; a SPUI would fit well here, provided the left-turn volumes are pretty high. The footprint is a bit bigger, but you can put some nice plantings in the islands and the traffic problems will disappear (temporarily, they always come back...) 
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Nov 16, 2009 02:35
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That looks like a good solution for that spot. The only issue I see with it is that they would probably have to close off the intersection to build it (have to dig tunnels in the middle), and I doubt they could get away with that for more than a few weekends there. Since I know they're actually doing some construction in the area now, I did a bit of searching today and found that they're building this:  Same general idea with the grade-separation, but I guess this would allow the intersection to be used during construction most of the time because the tunnels are off to the sides and they are right next to the existing ones. It just seems to be missing a way to go left from the south road, but maybe that had low traffic. Your solution looks cleaner and less complicated though 
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Nov 16, 2009 20:57
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Entropist posted:That looks like a good solution for that spot. The only issue I see with it is that they would probably have to close off the intersection to build it (have to dig tunnels in the middle), and I doubt they could get away with that for more than a few weekends there. Huh, that's pretty weird. It looks like they're sending through traffic on the north-south road around the intersection itself. It will be easier from a constructability standpoint (one of the tunnels goes under an existing bridge, the other could be done one half at a time). All the same, as a driver, it wouldn't be immediately apparent where to go, and, without proper signage, this could lead to confusion and accidents. As to the lack of left turn access, it seems you could go through and effectively do a U-turn, then a right turn, thanks to the new road they're building near the top of that picture.
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Nov 16, 2009 22:57
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It will be pretty confusing, the signage is usually good here but that won't help everyone. Just the fact that it'll be different than before is going to confuse some people. Fortunately the thing crossing all those lanes in the north doesn't seem to be a road. If it was a signalized intersection it would back traffic up into the other intersection since it's pretty close, and it would be kind of complicated with all the separated lanes depending on how much left and right turning is allowed. On Street View there's a brand new bike and pedestrian tunnel there. They just did a terrible job at drawing that plan image I guess. Heh, how did I miss this before, the construction work is clearly visible on Street View: http://maps.google.com/?ie=UTF8&hq=...121.59,,0,13.61
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Nov 16, 2009 23:28
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Entropist posted:It will be pretty confusing, the signage is usually good here but that won't help everyone. Just the fact that it'll be different than before is going to confuse some people. Fortunately the thing crossing all those lanes in the north doesn't seem to be a road. If it was a signalized intersection it would back traffic up into the other intersection since it's pretty close, and it would be kind of complicated with all the separated lanes depending on how much left and right turning is allowed. Ah, that rules out U-turns, then. I'll still defer judgment to the guys holding the turning counts ----- Our Crumbling Infrastructure Months ago, you asked about the state of our bridges, and I responded with some statistics that implied, more or less, that things don't look good. Well, at the moment, I'm involved in no fewer than four emergency bridge jobs. Anyone who lives in Connecticut, pay close attention, because you may want to change your commutes. Route 151 in East Haddam - Broken, busted, kaputt. We put up barricades and signs and cones, but people GOT OUT OF THE CAR AND MOVED THEM so they could drive over a broken bridge. Now there are concrete blocks instead. We got complaints from literally hundreds of people that they should be allowed to drive over the broken bridge. Route 42 in Cheshire - Culvert's been broken for a long time, and we just had a 6-day detour to fix it. You could go around the work site on local roads and only go a mile out of your way, but we decided on an all-state-roads detour that took traffic 9 miles through 3 towns. Like I said, sorry about that one. I-95 in Old Lyme - Two of the overpasses here were struck by trucks, and that did some major damage. Half of the bridge is roped off with cones, and we'll be replacing a couple of the beams... in Spring, or whenever we can afford it. Route 49 in North Stonington - A culvert here has all but given out. There's a hole in the roof of the culvert, and the inspector stuck his arm in up to the elbow. There's a big sag in the road. Rocks are sticking through the corrugated iron culvert wall. Our solution? Stick up a "BUMP" sign. Yep, that should do it. Now, why are our culverts failing? Well, back in the day, we decided that culverts (bridges under 20 feet, basically) didn't need to be inspected. Yes, go ahead and read that again. No need to inspect these thousands of small bridges under pretty much every road in the state. Smart, eh?
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Nov 17, 2009 04:55
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Cichlidae posted:Route 151 in East Haddam - Broken, busted, kaputt. We put up barricades and signs and cones, but people GOT OUT OF THE CAR AND MOVED THEM so they could drive over a broken bridge. Now there are concrete blocks instead. We got complaints from literally hundreds of people that they should be allowed to drive over the broken bridge. Just down the street right in front of my friend's house they were doing a major drainage project that had the road (normally very busy) closed for two or three months. Just down from my friend's house they were digging a ginormous loving hole across the length of the road for these massive concrete drainage tubes to go into. They'd cover it with steel plates whenever they weren't working on it, presumably to keep neighborhood children from tumbling in. This part of the road was partially blocked by concrete barriers, but part of it was just movable barrier so the constructions crews could get in and out. So my friend saw the same situation you described dozens of times a day. Because, you know, there's no way putting a couple of tons of weight at the edges of a huge hole on the road could possibly be a safety risk, right? (Granted, in this case they probably engineered the hole for this eventuality.) The best part is, in the time it took them to stop, get out of the car, move the barrier on one side, then the other, then get back in the car and drive through, they could have just driven through the detour one block over. Also, they would never replace the barrier, so the next dumbass that drives through might not even realize the thing is supposed to be closed off at all.
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Nov 17, 2009 06:25
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Cichlidae posted:Ah, that rules out U-turns, then. I'll still defer judgment to the guys holding the turning counts Well, it sounds better than what Rhode Island is doing. I'm sure you know about the I-95 bridge in Pawtucket, which has been weight limited. Big trucks can't go over it, but cars can. They've got traffic signs everywhere trying to detour trucks, but apparently it's such a big thing that they can keep two to four state police officers there, full time, to pull over big rigs. And from the traffic signs, it's a $3,000 fine. They've been doing this for two years, and every single time I drive by they've got a truck pulled over. Surely, with all the trucks they've pulled over in two years, they've made enough money to fix the bridge? Even assuming just one truck a day, that's 365 * 2 * 3000 = $2,190,000 And that's just one truck a day. How much will it cost to repair the bridge, and am I being cynical by thinking they'd rather fine truck drivers and pocket the profits, instead of actually fixing the problem?
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Nov 17, 2009 06:59
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Choadmaster posted:Just down the street right in front of my friend's house they were doing a major drainage project that had the road (normally very busy) closed for two or three months. Just down from my friend's house they were digging a ginormous loving hole across the length of the road for these massive concrete drainage tubes to go into. They'd cover it with steel plates whenever they weren't working on it, presumably to keep neighborhood children from tumbling in. This part of the road was partially blocked by concrete barriers, but part of it was just movable barrier so the constructions crews could get in and out. It's not just drivers, either. I had the same experience working at a supermarket back in the day. A big display rack of salad dressing was knocked over, and the floor was covered in oil. I barricaded off the section with signs and empty shopping carts, and people would just move them out of the way and wade through the slippery section instead of going 10 feet to the side. Pagan posted:Well, it sounds better than what Rhode Island is doing. I'm sure you know about the I-95 bridge in Pawtucket, which has been weight limited. Big trucks can't go over it, but cars can. They've got traffic signs everywhere trying to detour trucks, but apparently it's such a big thing that they can keep two to four state police officers there, full time, to pull over big rigs. And from the traffic signs, it's a $3,000 fine. They've been doing this for two years, and every single time I drive by they've got a truck pulled over. Surely, with all the trucks they've pulled over in two years, they've made enough money to fix the bridge? Even assuming just one truck a day, that's 365 * 2 * 3000 = $2,190,000 And that's just one truck a day. How much will it cost to repair the bridge, and am I being cynical by thinking they'd rather fine truck drivers and pocket the profits, instead of actually fixing the problem? $2 million really isn't enough money to fix a big bridge like that under heavy traffic, and, even if it were, I'm sure the police spend every dime of that before RIDOT would have any chance to use it. A great deal of Rhode Island's bridges are in terrible shape. There was one really bad batch of concrete decades ago that was used on the Washington Bridge and many of the Route 10 overpasses. You could go on the bridge and crumble it with your fingers! The DOT knew about this, but couldn't afford to fix it until recently (and the Washington Bridge is still under construction, right?) Then, there's the (old) Providence River Bridge. I don't know if you've ever been underneath, but it's been on temporary shoring for years, with hundreds of thousands of cars driving over it every day. There's one overpass down in Narragansett (on-ramp to Route 1 from Route 108) that's been shored up with wood timbers in a similar manner because the concrete columns are completely spalled, and the salt air has corroded the rebar through and through. I certainly didn't feel safe driving under or over that, because one decent earthquake could probably take it down. Connecticut at least has a fund for emergency jobs like this, but Rhode Island can't afford the $1 million plus (up to a hundred million for the huge bridges) every time a bridge starts failing inspections. I'm sure that it'll only take one collapse to change peoples' minds, but, really, why should we have to wait for that?
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Nov 17, 2009 13:17
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Cichlidae posted:I'm sure that it'll only take one collapse to change peoples' minds, but, really, why should we have to wait for that? Minnesota still hasn't replaced the US52 bridge which was in far worse shape than 35W. This bridge is notable for nearly collapsing in 1975, saved by a temporary patch that has never been replaced. They claim replacement in 2011, but I'll believe it when I see it.
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Nov 17, 2009 19:19
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This may be something that only applies to NJ, but whats the deal with all the pink center lines getting painted on the roads next to or between the double yellow lines lately?
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Nov 18, 2009 23:04
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Alpine Mustache posted:This may be something that only applies to NJ, but whats the deal with all the pink center lines getting painted on the roads next to or between the double yellow lines lately? No idea, I've never seen or heard of that here. It could be utilities, though. They use pink paint here to denote underground and overhead utilities. It's a little odd to have them running dead center down the middle of the road. Traditionally, they were installed here on the side of the road that gets more direct sunlight, so the ground would be easier to excavate in Winter. Are these lines spraypaint or epoxy? Are they really straight, or do they zigzag or branch?
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Nov 18, 2009 23:54
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Cichlidae posted:No idea, I've never seen or heard of that here. It could be utilities, though. They use pink paint here to denote underground and overhead utilities. It's a little odd to have them running dead center down the middle of the road. Traditionally, they were installed here on the side of the road that gets more direct sunlight, so the ground would be easier to excavate in Winter. Very straight, the ones i have seen look like spray paint. And in the places i have seen it, the double yellow lines looked spray painted too.
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Nov 19, 2009 01:42
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Do you know what those lines painted in a triangular shape perpendicular to a street are for? They're only used in two places in San Diego that I can think of and one of them was added very recently. Basically they look like this in each lane.code:dexter fucked around with this message at 02:16 on Nov 19, 2009 |
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Nov 19, 2009 02:11
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dexter posted:Do you know what those lines painted in a triangular shape perpendicular to a street are for? They're only used in two places in San Diego that I can think of and one of them was added very recently. Basically they look like this in each lane. Those mean "slow down/use caution." Often used before sharp curves or, around here, crosswalks. For those of us in Connecticut, you can find them at the Pratt and Whitney plant in East Hartford. Generally, the lines get closer together as they go. A similar thing I encountered in France: raised bars in the ground on rural roads approaching a village. Wakes you up and reminds you to slow down before the village. Cichlidae fucked around with this message at 02:35 on Nov 19, 2009 |
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Nov 19, 2009 02:28
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